Topic: battery is dead THEN ALiVE!

[hermanlikethemonster]

Hi, I know that this touches on topics that are repeatedly dealt with in the forum. That being said it seems different somehow. I have a 1973 cb500. It always had a charging issue. The bike sat for a long while and I am bringing it back to life. I bought a new regulator from Oregon. I have new plugs and battery. The bike is firing really only on two cylinders well. The inner two are ragged and fouling the plugs. The idle is ragged also...no surprise.

The bike starts great. I can ride around fine but at 35 MPH it is flat. It is totally choked. Any air kills the bike unless I am at 35+ in which case the bike is starving for air and if I open then choke no more flat spot. I think my air filter boots are leaking....

But that is not my issue. My issue is the bike will die after 10 minutes of riding and won't start -- electric will be totally silent and kick is fickle at best. Lights are off as if I have no power what so ever -- totally dead. BUT the next morning it starts right up! Using the electric start! As if no problem at all. Where did my power go after the 10 minute ride? How does the fuel problem translate into a dead battery?

thanks for your ideas.

- herman

[TwoTired]

Alternator doesn't charge bike at idle.
35MPH in top gear is pretty much idle RPM.
While you are riding, the battery is depleting.
A depleted battery yields weak or no spark.
A depleted battery will recover somewhat as the internal chemicals redistribute while sitting unused.  (It is actually a chemical storage device that produces/expends electrical energy during use.)

If you value your battery, you will use an off bike charger to bring it to peak.
Then you will immediately do an RPM vs battery voltage check to determine at what RPM the alternator begins raising the voltage of the battery. (which indicates charging)

[hermanlikethemonster]

Thank you Too Tired. I misspoke I replaced the rectifier not the regulator. Anyway, I understand the "recharging" phenomenon at night and the rpm relationship. I will do my due diligence and check the loads and try and find the problem. Thanks for all your many posts.